【測定：簡単カーブトレーサ・アダプタの試作法】 abstract This Blog explains how to make a simple curve tracer adapter. This curve tracer adapter was designed in the 1970s. So, there is no IC in it. Instead, this is a very good use of UJT. The circuit is simple, but I think it still works well today. I also dealt with how to modify the cheap oscilloscope, which is an essential part of the curve tracer. Even a

【DDS：AD9833を使ったDDSモジュールのススメ】 abstract Try the DDS module using the AD9833. I bought this DDS module from a mail order company in China. It is very inexpensive, but the performance is good. The signal obtained by this DDS module has good frequency accuracy and the spectrum of the signal is clean. I would like to explore the basic use of the DDS module first. (2020.12.15 de JA9TTT/1 Takahiro Kato)

【ECL ICを使ったRF-PSNの製作】   I use the ECL of a fast logic IC to make the 90° phase shifter needed to generate a PSN type SSB.　It didn't work properly at first because it was built on the breadboard. Even though it was a logic IC, it was accompanied by an oscillation phenomenon. The cause was unexpectedly simple, ECL-IC is an internal structure like an analog IC.    It's like a series of

【回路検討：ゲルトラで作るパワー・アンプ】 abstract Making an RF Power Amplifier with Germanium Transistors. Germanium transistors are vulnerable to high temperatures, so they are mounted on a large heat sink.　The Π605 is made in the Soviet Union, so I had to make a little effort to mount it on a heat sink. Now that it went well, let's try a collector grounded type RF Power Amplifier. (2020.11.30 de JA9TTT/1

【ゲルトラで作る送信機】 (abstract) An experiment in making a transmitter using Soviet-era germanium transistors. There are no germanium transistors in the Western world that can outout a lot of power in RF. The Western world, including Japan and the U.S., gave up on germanium transistors too early. The Soviet Union had them. I'm going to make a practical CW transmitter with germanium transistors of Soviet

  Photo : 2021.06.01 14:04 JST at Sogenji Temple Ota-City

【トランジスタ・カーブトレーサ：調査編】 abstract I'm going to make a simple curved tracer. A curve tracer is a measurement device to easily investigate the characteristics of semiconductors such as transistors or FETs. It is difficult to make a full-scale curve tracer. However, if the functions are limited and the performance is limited to the required range, it is not too difficult to make it. I will briefly

Photo : 2021.05.02 09:30 JST at my garden

【HAM Bandが拡張されました】 The Japanese Amateur Radio Band (HAM Band) has been expanded.　Expanded are the 160 meter band and the 80 meter band.　In the past, when communicating with DX stations, it was necessary to be on-air at a "split frequency". From now on, JA stations will be able to air at 1800 to 1875kHz, and the 1840kHz FT8 mode will be very popular with JA stations.   (2020.04.21 

【MC3340Pを使ったAM Radioの試作】   I built a prototype AM radio using Motorola's IC: MC3340P in the AGC circuit. The purpose of this is to test if the MC3340P electronic attenuator can be used for radio and wireless communication devices. The MC3340P is a low-frequency device. As a result of my trial, I found out that it can be used for high frequency circuits as well.  I think it is possible